Differences in Pathology and Mutation Status Among Colorectal Cancer Patients Younger Than, Older Than, and of Screening Age

BACKGROUND

Screening protocols for colorectal cancer are broadly recommended and effective in reducing mortality. However, populations from different age groups can harbor distinct pathologic and molecular profiles that can also be influenced by screening and polyp resection, especially in older ages.

PATIENTS AND METHODS

We retrospectively analyzed tumors from stage IV colorectal cancer patients from a central pathology laboratory in Brazil that is a reference for mutational profiling countrywide. Patients were classified into age groups as follows: prescreening age (PrSA; < 45 years old), screening age (SA; 45-75 years old), and postscreening age (PoSA; > 75 years old). Every tumor was centrally reviewed by the pathologist. Groups were compared regarding clinicopathologic features, and the presence of RAS (renin-angiotensin system) and BRAF (v-Raf murine sarcoma viral oncogene homolog B) mutations.

RESULTS

We included 1635 patients (215 PrSA, 1213 SA, 207 PoSA). There was no difference among groups regarding sidedness (P = .65) and KRAS (Kirsten rat sarcoma viral oncogene) mutations (P = .57). Stage IV disease at diagnosis (P = .04), the presence of a signet-ring cell component (P < .001), and poorly differentiated tumors (P = .02) were most common in young patients, while BRAF and NRAS (neuroblastoma RAS viral (v-ras) oncogene homolog) mutations were significantly more common among PoSA patients (P = .002 and .03, respectively). When divided by age decade, KRAS mutations seem to have a stable frequency among all ages, while the BRAF mutation rate increased with increasing age.

CONCLUSION

BRAF mutations are more frequent among PoSA patients, and this seems to be a continuous trend. PrSA and PoSA patients seem to present a distinct profile from SA, including differences in molecular and pathologic aspects. These findings could impact the frequency of screening tests among different age groups.

Male breast cancer: Epidemiological evaluation and clinical outcomes

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Background: Male breast cancer (BC) is a rare neoplasia, with a risk of 1:1.000 in USA. Data from Sao Paulo Cancer Registry has shown that BC adjusted incidence rates is about 1.21 per 100,000 at the period from 2001 to 2005, but there is no incidence data for the whole country. Methods: We conducted a unicentric retrospective cohort, with histologically proven male BC patients whose first appointment was between 2008 and 2018 at Instituto do Câncer do Estado de São Paulo in Brazil. The primary endpoint was OS according to metastatic status and initial staging. OS and RFS were analyzed by Kaplan–Meier method and the difference calculated by log-rank test; reported hazard ratios by univariate Cox Models and P-values by score test. Multivariate analysis was calculated through COX regression. Results: 89 male BC patients were accessed, average age at diagnosis was 63.3 yeas-old. 84.2% had carcinoma of no special type (88,7% estrogen positive receptor, 84,2% progesterone positive receptor). When Charlson Comorbidity Index (CCI) was calculated, most (23.5%) were ≥ 7 (10-year survival: 0%), being 17.9% stage IV. Mastectomy was performed at 73% patients, 38.2% received adjuvant chemotherapy; 44.9% received adjuvant radiotherapy and 64% received adjuvant endocrine therapy (94.7% tamoxifen). For metastatic disease, endocrine therapy was the first option in 52%. Median OS was 75 months (95% CI, 39.2-110.7) in M0 and 39 months (95% CI, 25,2–52,8) in M1 ( p = 0.001). CCI showed be an independent death factor (HR 0.37, 95% CI, 0.17-0.8, p = 0.011). Median RFS was 97 months [95% CI, 47.3–146.7]. When BMI was evaluated for patients with obesity (> 30) there was no difference in disease relapse ( p = 0.29). Conclusions: Our results are consistent with those from previous literature, regarding histology, biomarkers and later stage at diagnosis. A quarter of our patients had high CCI and this could had impacted on best treatment option choices. Treatment approaches use to be similar from those of female population. However, as disease biology and hormonal physiology are different between gender, there is a lack of specific protocols and trials in male population.

Stereotactic radiotherapy in oligometastatic (OM) gastrointestinal (GI) tumors: A single institution retrospective analysis

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Background: Metastatic GI cancers are mainly treated with systemic treatment (ST), in selected patients (pts), surgery is considered depending on pts characteristics and institutional preferences. Stereotactic Radiotherapy (SRT) is a growing treatment option in such landscape aiming to improve local disease control and maximize ST results for oligometastatic pts. Methods: This is a single center retrospective study. Data were collected from sequential pts with GI tumors who underwent SRT for OM-GI cancers from May 2014 to July 2019. Information was collected on pts characteristics, primary site, clinical staging at diagnosis, sites undergoing SRT, whether there was progression after the first SRT, time between the first SRT and progression and the last follow-up date. Results: 381 pts underwent SRT in our center, of these, 75 pts had OM-GI tumors and underwent 120 courses of SRT. 50,7% were women, the median age at diagnosis was 60 years and the median follow-up was 36 months. 76% had colorectal cancer (CRC) being 26% from the right, 26% from the left colon and 30% were from the rectum, in 18% of the patients we could not determine sidedness. 35% already had metastatic disease at diagnosis. The lung was the site with largest number of lesions treated with SRT (50), followed by central nervous system (CNS) (42), bones (32), liver (29) and lymph nodes (16). After a median follow up of 15.3 months, 11% of patients were progression-free and only 24% had progressed on treated lesions. The median progression free survival following SRT was 4.5 months (0.6-45.8 range) for distant metastasis and was not achieved for treated sites. Conclusions: This retrospective study adds to the previous body of evidence supporting the use of SRT to improve GI cancer management. Detailed information on pts characteristics, pathology, toxicity and previous treatments will be presented.

Stereotactic radiotherapy (SRT) in oligometastatic (OM) colorectal cancer (CRC): Can we improve systemic therapy (ST) free interval?

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Background: Metastatic colorectal cancer is common disease that is treated mainly with systemic chemotherapy with or without target therapy combined with local therapies when feasible. Patients with OM-CRC may benefit from local treatments, classically surgery, but more recently SRT is also showing to be effective. We aimed to access the benefit of SRT in patients (pts) with OM-CRC that where not candidates for surgery. Methods: This retrospective study evaluated all the pts with CRC from a single institution that did SRT for OM-CRC. SRT was done with 3D or IMRT/VMAT planning and daily volumetric image. 1-10 fractions were delivered aiming to keep BED > 100Gy10. Dose was decreased as necessary to respect the constraints and minimize toxicity. Progression free survival (PFS) was analyzed from SRT to first progression or death, ST-free survival (STFS) from SRT to the beginning on next ST line or death. Results: We evaluated 32 consecutive pts from Sep/2014 to Jul/2019. Forty-six courses of SRT where performed. Mean age was 56 ± 13y, 60% female and 65% had colon cancer. 52% had metastatic disease after radical treatment. 63% were off ST by the time of the SRT. SRT treatment sites were lung and liver in 28%, bones and lymph nodes 13%, and CNS 11%. 72% of pts had only 1 treated lesion and 70% did 1 SRT course. Most commonly used regimens were 3 x 10-18Gy (35%), 4 x 10-12Gy (15%) and 5 x 7-10Gy (22%). 37% of treatments had BED≥100Gy10 and 78% were done with IMRT/VMAT. With a median follow-up of 16.1m (IQR 8.2-32.7), the median PFS was 5.4m (95% CI 4.1-11.0) and STFS was 12.7m (95% CI 0.8-24.5). Patients with multiple SRT courses had longer interval between disease progression and starting the next ST line (median 2.2 vs 12.4m). Pts that where on ST holidays before SRT had higher STFS (HR = 0.24 95% CI 0.1-0.6, p = 0.001) probably due to selection bias (lower disease volume). The 3y OS was 71%, median was not reached. Conclusions: Local treatment with SRT for OM-CRC showed to be feasible and safe with promising PFS and OS that deserves further investigation. The median STFS superior to a year suggests that SRT can influence OM-CRC treatment positively, possible impacting quality of life and even treatment costs.

Functional pancreatic neuroendocrine tumour causing Cushing's syndrome: the effect of chemotherapy on clinical symptoms

Background

Neuroendocrine tumours (NETs) are a heterogeneous group of diseases that can originate from any part of the gastrointestinal tract, bronchi, thyroid and pancreas. These tumours may be functioning or not depending on their ability to produce active substances, such as adrenocorticotrophic hormone (ACTH). ACTH-producing pancreatic neuroendocrine tumours are rare, with limited data about effective antitumor therapies.

Case Report

A 58-year-old man with a history of type-2 diabetes mellitus and arterial hypertension was diagnosed with Cushing’s syndrome (CS) secondary to an ACTH ectopic production from a well-differentiated neuroendocrine tumour of the pancreas metastatic to the liver. The patient underwent initial body-caudal pancreatectomy, splenectomy and hepatic nodulectomy with subsequent recurrence. Hepatic embolisation and somatostatin analogues were used to control CS but without success. Bilateral adrenalectomy led to CS control, while capecitabine and oxaliplatin (CAPOX) was effective in controlling tumour growth and ACTH production.

Discussion

ACTH-producing pancreatic neuroendocrine tumours are rare, aggressive and difficult to treat with available therapies. In settings of limited resources, such as in developing countries where targeted therapies are not available, cytotoxic chemotherapy with CAPOX represents a good and inexpensive option to control ACTH-producing pancreatic neuroendocrine tumours. Because of its complexity, the management of this tumour should be performed by multidisciplinary teams.

Refractory hypoglycemia in a patient with functional adrenal cortical carcinoma

Adrenacarcinomas are rare, and hypoglycemic syndrome resulting from the secretion of insulin-like growth factor II (IGF-II) by these tumors have been described infrequently. This study describes the case of a young woman with severe persistent hypoglycemia and a large adrenal tumor and discusses the physiopathological mechanisms involved in hypoglycemia. The case is described as a 21-year-old woman who presented with 8 months of general symptoms and, in the preceding 3 months, with episodes of mental confusion and visual blurring secondary to hypoglycemia. A functional assessment of the adrenal cortex revealed ACTH-independent hypercortisolism and hyperandrogenism. Hypoglycemia, hypoinsulinemia, low C-peptide and no ketones were also detected. An evaluation of the GH-IGF axis revealed GH blockade (0.03; reference: up to 4.4 ng/mL), greatly reduced IGF-I levels (9.0 ng/mL; reference: 180-780 ng/mL), slightly reduced IGF-II levels (197 ng/mL; reference: 267-616 ng/mL) and an elevated IGF-II/IGF-I ratio (21.9; reference: ~3). CT scan revealed a large expansive mass in the right adrenal gland and pulmonary and liver metastases. During hospitalization, the patient experienced frequent difficult-to-control hypoglycemia and hypokalemia episodes. Octreotide was ineffective in controlling hypoglycemia. Due to unresectability, chemotherapy was tried, but after 3 months, the patient's condition worsened and progressed to death. In conclusion, our patient presented with a functional adrenal cortical carcinoma, with hyperandrogenism associated with hypoinsulinemic hypoglycemia and blockage of the GH-IGF-I axis. Patient's data suggested a diagnosis of hypoglycemia induced by an IGF-II or a large IGF-II-producing tumor (low levels of GH, greatly decreased IGF-I, slightly decreased IGF-II and an elevated IGF-II/IGF-I ratio).

LEARNING POINTS

Hypoglycemyndrome resulting from the secretion of insulin-like growth factor II (IGF-II) by adrenal tumors is a rare condition.Hypoinsulinemic hypoglycemia associated with hyperandrogenism and blockage of the GH-IGF-I axis suggests hypoglycemia induced by an IGF-II or a large IGF-II-producing tumor.Hypoglycemia in cases of NICTH should be treated with glucocorticoids, glucagon, somatostatin analogs and hGH.